Hello
We ship our software with notifications working. This is an important function of the software and many clients depend on it. So notifications work. The notifications do not work for you because you insist to use a browser which is not supported and to make everything worse, you want to use on an ipad. So you are putting bad ingredients in the mix.
1. Find a chrome browser and see if notifications work. Once you see notifications working, then the server is ruled out.
2. Next I would install Chrome on IPad So at least we understand if you can use the ipad or not.
Notifications depend on many factors - security settings, browser version etc. So given there are many points of failure, you need to start off from a baseline point - a point where we see something work.
I can also offer that you create 2 extensions for us to test. Contact me privately and we can organize a test. Like this we can rule out whether the notifications are working on your instance.
Thanks for reporting.